The photovoltaics sector was bullish thanks to good revenue growth in May and expectations that Taiwan's solar product makers will benefit from the U.S. decision to impose anti-subsidy tariffs on Chinese solar equipment imports.

Shares of touch panel maker TPK Holding Co. (宸鴻), a supplier of Apple Inc., also gained 7 percent to close at NT$258 after the company reported a 20.7-percent month on-month growth in consolidated sales in May. TPK is expected to gain from the launch of Apple's new products in the second half of this year.